1. Field of the Invention
The present disclosure relates to a pharmaceutical composition comprising a composite extract of Rehmannia glutinosa and Pueraria lobata for preventing or treating menopausal symptoms, and a method of preventing or treating menopausal symptoms.
2. Description of the Related Art
Population ratio of aged people over 65 in 2005 in Korea takes 9.1% and it is expected to become an aged society with more than 14% of population ratio in 2019. Also, average female life expectancy is 80.4 in 2002, thus particular attention on female's healthy life for 30 years after menopause is required.
The World Health Organization (WHO) defines menopause as it is an end of childbearing period because of termination of estrogen secretion due to ovarian failure, and transition period from adolescence to senescence. Generally, climacterium is a kind of endocrine symptoms and a transition period where physiological and sexual functions are being reduced or lost due to overall and gradual recession of ovarian function, and as a climacteric process, menopause, i.e. a permanent termination of menstruation that occurs after ovarian failure, comes succeedingly. Acute and chronic symptoms can be caused by decrease of estrogen production and hormonal changes such as increase of follicular stimulating hormone (FSH), luteininzing hormone (LH), etc. Postmenopausal women are encountered markedly increasing likelihood of psychologic and emotional symptoms, i.e. fatigue, agitation, insomnia, attention deficit, depression, amnesia, headache, anxiety, and nervousness or microcardia due to rapid decrease of estrogen, and likelihood of occurrence of fatigue and agitation according to sleep deprivation, occasional vertigo, paresthesia, palpitation and tachycardia, nausea, constipation, diarrhea, arthralgia, myalgia, cold hypersensitivity in hands and feet and weight increase, and uterus involution due to relapsing hot flush also markedly increase. In addition, osteoporosis can easily be induced and mortality increases due to cardiovascular diseases such as heart disease, hypertension and stroke (Kalin MF & Zumoff B. Steroids 55:330-352, 1990). Additionally, changes in skin and genitourinary system are incurred, and onset possibility of autoimmune diseases, cataract and colorectal cancer increases.
Furthermore, production of estrogen, (i.e. female hormone) rapidly decreases during menopausal period. There is a problem with climacteric women that cholesterol is easily accumulated in their blood vessel because estrogen functions as protecting blood vessel by decreasing cholesterol level through blocking accumulation of visceral fat. Recently, a research paper reported that onset possibility of cardiovascular diseases is higher for climacteric women compared to perimenopausal women in same age.
Hormone replacement therapy and treatment with NSAIDs and the like have been developed as therapies for improving menopausal symptoms, and the hormone replacement therapy that administers estrogen is known as the most effective method among the therapies. However, as disclosed in theses such as Risks and Benefits of Estrogen Plus Progestin in Healthy Postmenopausal Women (JAMA, Jul. 17, 2002-Wol 288, no3), it is known that hormone therapies using estrogen etc. may cause various risks. In detail, long-term use of the drugs according to said therapy could incur endometrial cancer, breast cancer, hypertension, thrombosis, biliary, urinary calculi, etc. and also, menstrual bleeding can be incurred, and a problem lies that drugs cannot be administered without doctor's prescription because of the side effects such as ovarian hyperstimulation and the like. To overcome such problem caused by the drug therapy, there are attempts to develop improving agents for female menopausal symptoms with natural crude drugs as active ingredients.
For example, Korean Patent No. 10-0419121 discloses a crude drug composition comprising folium phyllostachyos, Angelica gigas root, Cnidium rhizome, Paeonia lactiflora root, Atractylodes rhizome white, Poria cocos, Red ginseng and soybean extract as main ingredients for improving female menopause symptoms through action that increases female hormone (i.e. 17β-estradiol).
Rehmannia glutinosa is a steamed and dried root of medicinal plants belongs in the Scrophulariaceae family which is used as a medicinal ingredient in field of oriental medicine. It is known to have efficacy of treating chilling pain in waist and knee, dizziness, and blackening hair. It has been used for various chronic diseases including internal body heat due to feeble health condition, dry throat, thirst, etc. Iridoid glucosides such as catalpol, leonuride, aucubin, mielittoside, rehmannioside A, B, C and D; and saccharides such as stachyose, raffinose and sucrose are main ingredients of Rehmannia glutinosa. Moreover, it is reported that there are also mannitol and 10 types of amino acids other than the above.
Radix Puerariae is a root of kudzu vine (i.e. deciduous climbing plant) belongs to the Leguminosae family. Radix Puerariae has efficacy in alcohol poisoning recovery, diaphoresis treatment, macula treatment, thirst quenching, pus detoxication and treatment, and diarrhea treatment. Thus it has been frequently used for treating cold, emesis, measles, oligodipsia, diarrhea, angina pectoris, hypertension, migraine, retinal artery occlusion, sudden deafness, alcohol intoxication, etc. clinically. Active ingredients of Radix Puerariae include as flavonoids such as daidzin, daidzein, puerarin and puerarin xyloside; and a large volume of starches.
However, no studies on the composite extract of Rehmannia glutinosa and Pueraria lobata are reported so far. Consequently, the present inventors completed the present disclosure upon confirmation that the composite extract can improve weight increase which is a menopausal symptom, and decrease blood cholesterol and serum alkaline phosphatase while studying on effects of the composite extract of Rehmannia glutinosa and Pueraria lobata. 